"Isotope" Essays and Research Papers

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Mass Spectrometer

spectrometer has been a universal research tool, mostly involved in comparing the masses of atoms. Since the invention of this tool about 100 years ago, the mass spectrometer has been responsible for the description of molecular structure, the detection of isotopes, the classification of atomic weights and more! The mass spectrometer has been vital to chemistry, and will continue to do so for more years to come. The history of the mass spectrometer starts with a man named Sir Joseph John Thompson. Thompson...

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Development of Atomic Theory

DEVELOPMENT OF THE ATOMIC THEORY Part A: HISTORY * 1869: Mendeleev formulated the Table of the Elements - listing them by their atomic weight and grouping them with similar characteristics. * 1897: JJ Thomson discovered electron and isotopes, and invented the mass spectrometer. * 1898: Marie Curie discovered and isolated radium, a new element which unprompted disintegrated into other elements. This proved that the atoms of one element at least were not indivisible. * 1911: Ernest...

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Barium Essay for Chemistry

baryta or BaO. But it was discovered in 1779 by Carl Scheele. Barium is classified as an alkaline-earth metal. Its atomic number is 56 and it is the fifth element in group 2.Natural Barium is made up of a mixture of seven stable isotopes, there are thirteen radioactive isotopes known to exist. Barium has never been found in nature in its pure form. When Scheele discovered barium in the 1700's he could not isolate it he could only isolate the barium oxide. Another person to isolate the barium oxide was...

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Atomic Theory - Essay

Dalton’s theory are that his second law that all atoms of the same element are the same is false because today we have found that there are other kinds of atoms called isotopes. An isotope is an atom that has the same amount of electrons and protons, but it has more neutrons that increase its atomic mass. Some examples of isotopes are Carbon 12, carbon 13, carbon 14, Uranium (234, 235, and 238) and lithium (6, 7). Carbon 14 is especially useful because we know its rate of decay and can use to find...

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Atomic Structure Notes

protons than electrons Isotope: an atom that has the same 3 of p+ (same element) as another atom but a different # of N than that atom. Atomic mass unit (amu) a unit of mass used for atoms, molecules, ions, p+, n, e- isotopes etc C-12 is the standard for atomic masses. Mass of exactly 12 amus Atomic mass unit is 1/12 of the mass of a C-12 atom Ex: M=A+N 12= 6+6 Atomic mass = the average mass, based on the masses of all the isotopes for the element. (the % of each isotope in nature influence...

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Atomic Number and Tellurium

of all the protons, electrons, and neutrons within the atom at rest. As shown on the periodic table, tellurium has an atomic number of 52, and a mass of 127.60. Isotopes are atoms with the same number of protons, but have different number of neutrons. Tellurium has 33 isotopes and when it occurs naturally it has a mix of eight isotopes: 120Te (0.1%), 122Te (2.6%), 123Te (0.9%), 124Te (4.8%), 125Te (7.1%), 126Te (19.0%), 128Te (31.7%), and 130Te (33.8%). Tellurium’s usual and most commonly found...

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Honors Chem

nitrogen – 16 3. All isotopes of technetium are radioactive, but they have widely varying half-lives. If an 800.0 g sample of technetium-99 decays to 100.0 g of technetium-99 in 639 000 yrs, what is its half-life? 800g/2 400g/2 200g/2 100g…3 half lives have passed 639,000years/3 half lives = 213,000 years half-life of technetium – 99 4. A 208 g sample of sodium-24 decays to 13.0 g of sodium-24 within 60.0 hrs. What is the half-life of this radioactive isotope? 208g/2 104g/2 52g/2...

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Half-life of a Radioisotope

The Half-Life of a Radioisotope: 10-22-14 Abstract: The half-life of a radioisotope is the time required for half the atoms in a given sample to undergo radioactive, or nuclear decay. The amount of radioactive isotope remaining can be calculated using the equation, t1/2 = .693/K. A sample data set was provided due to safety concerns. Using the data set, a half-life of 14.27days -1 was calculated using graphical linear regression analysis. Introduction: The purpose of this experiment is to...

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Isotopes and Its Uses

ISOTOPES History of the term: In the bottom right corner of JJ Thomson's photographic plate are the separate impact marks for the two isotopes of neon: neon-20 and neon-22. The term isotope was coined in 1913 by Margaret Todd, a Scottish physician, during a conversation with Frederick Soddy (to whom she was distantly related by marriage).[4] Soddy, a chemist at Glasgow University, explained that it appeared from his investigations as if each position in the periodic table was occupied by multiple...

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Peaceful Uses of Nuclear Energy

focus will be on the generation of electricity using nuclear energy in nuclear power plants as it is one of the main peaceful uses of nuclear energy. Electricity is generated using isotopes of certain atoms (elements). Although atoms are tiny, they have a large amount of energy holding their nuclei together. These isotopes can be split and will release part of their energy as heat. This splitting is called fission. A series of fissions is called a chain reaction. This chain reaction creates a great...

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